This invention relates to a method of manufacturing a magnetic head to be used in various recording/reproducing instruments such as cassette tape recorders and video tape recorders and streamers associated with a computer for preventing accidental erasure of data stored in a hard disc unit of the computer.
Japanese Patent Publication No. (Sho) 51-44648 discloses a process for manufacturing the magnetic head comprising the steps of preparing a magnetic ring core element consisting of a pair of half bodies and providing a prescribed gap, and inserting and securing the ring core element in a slot formed in a parallelepiped block or slider of magnetic material. Into the slot is inserted a glass rod which is then melted and solidified so that the slot is filled with the glass material. The glass material in the slot is formed to form a groove of a width identical to a thickness of the magnetic core element and a depth greater than the slot. The core element is fitted into the groove and fixedly positioned by remelting and resolidifying the glass material. The slider is ground from the bottom side to expose the inserting end of the core element, thereby producing a head assembly. The head assembly may simply be used as a magnetic head. In other embodiments, one or more of the head assemblies are mounted in position on a base block to produce a composite magnetic head. The head assembly may include two or more of ring core elements fitted in slots or grooves extending in parallel in the slider.
According to this prior art, if the core element should be prepared with displacement in height with respect to the two half bodies, it would become difficult for the core element to be definitely positioned in the slot in the slider. If the base end of the core element fitted in the slider could not be maintained flush with the top side of the slider, a prescribed gap depth in the magnetic head would be impared, resulting in deterioration of characteristics of the magnetic head.
When producing the composite magnetic head, plural head assemblies are placed and secured on the base block with a jig providing a reference plane to be in contact with the side surface of the slider. This requires high working accuracy on the side surface of the slider, which will inevitably and considerably increase a manufacturing cost of the composite magnetic head. In case of degraded working accuracy on the side surface, the gaps in the ring cores in the respective head assemblies would not be aligned in parallel, which may cause azimuth loss. The above can also be said when a single head assembly is to be mounted in position on the base block.